An interior space of a vehicle has a predetermined size to accommodate a driver and passengers. The driver and passengers can enter the interior space of the vehicle by opening and closing doors which are installed at a vehicle body.
In a passenger vehicle, the doors for opening and closing the vehicle interior space may have a front door disposed at a front side in a longitudinal direction of the vehicle and a rear door disposed at a rear side in the longitudinal direction of the vehicle. The front door and the rear door are installed at the vehicle body to rotate via a hinge.
In a van which can transport more people, doors open and close an interior space with sliding movement forward and reward in a longitudinal direction of the van.
The sliding doors open the interior space by moving rearward in the longitudinal direction of the van and close the interior space by moving forward along the longitudinal direction of the van, thus fully opening the doors installed at the vehicle body even in a small opening and closing space.
However, the sliding doors for opening and closing the vehicle interior space require three supporting and guiding rails for supporting an upper portion, a middle portion and a lower portion of the doors and related components, thereby increasing the number of parts and the weight of the vehicle and decreasing the design freedom of the vehicle.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the disclosure, and therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.